Generally, for achieving spit roasting where chicken and the like are roasted on a spit, a roaster comprising a gas burner employing a gas as a heat source and a pair of support bars disposed above the gas burner is used. Such a roaster is designed to achieve roasting of spitted meats and the like over the gas burner by placing the spits across the support bars disposed above the gas burner with a predetermined distance defined therebetween.
A spit roaster employing a gas as a heat source enjoys wide use, since it requires a simple operation for old or consumed charcoal with, and also a sufficient caloric or heat input can be obtained. However, flames generated during combustion of the gas may have a high surface temperature, but they cannot send sufficient heat to the internal portions of the meata because of the wavelength characteristics to the gas. For such reason, the above construction involves a problem in that the surface of the meat will be burned or overcooked before sufficient heat goes through the meat as one may desire. In this respect, the use of a charcoal fire as a heat source for spit-roasting provides an advantage in that a sufficient amount of heat permeates the center of the meat by virtue of infrared rays emitted from the charcoal during burning. Moreover, the surface temperature of the charcoal fire is not very high, so that there is a relatively small possibility that the surface of the meat will be burned. Accordingly, it is well known through experience that the optimum waay of roasting a meat is to roast it over a charcoal fire in order to enhance the flavor of the meat. However, it has actually been difficult to use charcoal in an ordinary spit-roasting restaurant where the pursuit of profit is of primary importance due to the difficulty in controlling the caloric or heat output of the charcoal fire and the like, although it may be used domestically wherein considerable personal labor may be required in order to control the caloric or heat output. Furthermore, a large amount of smoke will be generated during roasting of the meat over the charcoal fire and such quickly permeates a small cooking space so as to deteriorate the cooking environment, and tends to continue spreading throughout the dining rooms of the restaurant so as to disadvantageously generate an offensive atmosphere for the visitors, or partrons. Still further, the use of a charcoal fire requires troublesome considerations, such as for example sufficient ventilation and the like when it is used within closed dining rooms of the restaurant since the charcoal generates harmful carbom monoxide gas during the initial stage of its burning. Thus, under the present circumferences, charcoal is not substantially used in restaurants in spite of a the known fact that the optimum way of roasting a meat is the use of charcoal fire.